Devices that fire frangible projectiles are known in the art. For example, paintball markers are used for marking in forestry and cattle ranching. Paintball markers have also become popular in a variety of targeting and simulated battle games (e.g., capture the flag). In some cases, law enforcement employs markers to aid in crowd control and other situations where less-than-lethal force is desired.
The markers launch a projectile typically using compressed gas, such as carbon dioxide or nitrogen. Compressed gas is supplied from a supply tank which is typically mounted to or carried with the marker. In some cases, the markers may be equipped with pressure regulators, which receive compressed gas at a relatively high pressure and deliver the gas at a reduced, more consistent pressure for propelling the projectile.
There are two main types of markers presently on the market. One type uses a hammer with a tripping mechanism to strike a firing valve, where part of the compressed gas is used to propel the projectile and another portion of the gas is used to return the hammer to a ready-to-fire position (i.e., “recock” the marker). This type of design causes kickback or recoil when recocking the marker.
The second type of marker includes a spool valve where the marker's bolt is utilized as a spool valve with sealing members placed on it. A disadvantage of this arrangement is that sealing members are the size of the bolt and require significant force to jump start bolt movement under pressure. Also, the lubrication state of O-rings effects velocity of the bolt. If the o-rings are dry, a large force is needed to move the spool-bolt combination forward to load the paintball into the barrel, which can cause paintball breakage. To reduce paintball breakage, soft o-rings with a very small squeeze are being used. This leads to another problem when using carbon dioxide (“CO2”) as a source of energy, because during rapid firing liquid CO2 imbeds with the sealing members, resulting in a loss of elasticity and leaks. Other pneumatic markers include complicated firing mechanisms. Drawbacks of these more complicated mechanisms include operating difficulty, frequent maintenance issues, and high manufacturing cost.
Another common problem with existing markers is breakage or rupturing of the frangible projectiles. The frangible projectiles commonly have a gelatinous or plastic shell designed to break upon impact. Typically, the shells are filled with a marking material, such as paint, and/or an immobilizing material, such as a noxious chemical. Projectiles drop by gravity force from a hopper (or are otherwise fed) into the marker's breech chamber. Typically, the firing mechanism includes a bolt that pushes the projectile into the barrel when the user pulls the trigger. In some cases, however, the projectiles become partially inserted into the breech chamber. When this happens, the bolt tends to chop or shear the projectile, which fouls the marker's breech chamber and barrel.
Existing markers have a cylindrical feed tube disposed usually on the top portion of the marker and perpendicular to the barrel. The upper portion of the feed tube is typically connected to a hopper. Since the feed tube has a cylinder extending into another cylinder formed inside the breech chamber, intersecting curves (rays) exist when viewed in three dimensional object geometry. The opening cavity of breech chambers in existing markers is made by using a ball end-mill, which is cylindrical in shape. The end mill has end flutes that are formed in a circular configuration, and when plunged into a solid material will form half of the sphere extending into a cylinder as shown in FIG. 37. In this particular case, the ball end mill plunges into the breech chamber body until it reaches the lowest point of the internal cylindrical surface of the breech chamber, where the cylindrical surface of the breech chamber is the extension of the barrel's cylindrical bore.
From a three dimensional geometry standpoint, this results in an intersection of two cylinders and the intersection of a cylinder with half of the sphere. The intersection of two cylinders results in elliptically-shaped curves. The intersection of a cylinder with a sphere has a parabolic curve in one of the views. In the scenario presented above, the projectile needs to drop all the way down to the point where the center of the projectile lies within the breech cylinder symmetrical line, which is an extension of the barrel's internal bore for loading the projectile to be fired. In a case when the projectile feed is provided by gravitational force, many times during rapid firing projectiles do not reach the point of readiness to be loaded into the barrel. Instead, the projectiles are still falling when the sliding bolt forces the projectile into the firing chamber through the elliptical/parabolic intersecting lines which are smaller in width than the diameter of the projectile causing paintball breakage.
Another common problem encountered with firing projectiles is accuracy. For example, paintball manufacturing often results in paintballs that are not perfectly round and can have significant variability in average diameter. Without wishing to be bound by a particular theory, Applicant believes this causes paintballs to start spinning during the loading operation into the firing chamber. Rotations of the paintballs are then further promoted when compressed gas is applied to fire the paintball. Applicant believes that excessive paintball rotation causes undesirable variation in trajectory (similar to how a soccer player tries to impart a curve in the ball path to avoid a goalie).
It therefore would be desirable to provide a novel projectile launcher that reduces recoil and paintball breakage.